User Manual

AS4000 Operations and Maintenance
Section
605-0000-431
6
. Issue 1.6. Date3/2/99
DLP-028
Page 19 of 22
REPLACING A MODEM SHELF
Tools required
ITEM DESCRIPTION SIZE
04 Screwdriver Pozidrive No 1 x 75mm
05 Screwdriver Pozidrive No 2 x 199mm
06 Screwdriver Pozidrive No 3 x 150mm
07 Screwdriver Flat Blade 3mm x 100mm
STEP PROCEDURE
Observe full ESD precautions.
To replace a faulty Modem Shelf proceed as follows:
1. Removing the Shelf
a) Check the delivery of equipment and unpack following the procedures outlined in
the CT I&C Manual
b) Remove the modem shelf front panel by disconnecting PL4
c) Remove the DC cable plug to the DC input socket PL6 and remove the crimped
cable screen earth to the lug positioned alongside PL6. See Figure 1-4.
d) Remove the cards from the shelf and place on ESP mat or in ESP bags /
containers
e) Remove the right hand side panel by unscrewing the six captive screws.
f) Remove the braided earth strap to the frame using a M4 screw and M4 nut as
shown in Figure 1-4.
g) Remove ribbons to JP3 and JP4. See Figure 1-6
h) Remove the element manager connector from PL5.
i) Remove the 2Mbit/s IN (SK16 - BNC or PL7 - Type 43) and 2Mbit/s OUT
(SK15 - BNC or PL8 - Type 43) connectors on the shelf interface connections
located at the right hand side of each modem shelf. See Figure 1-8 and Figure 1-10.
j) Unscrew the four crosshead screws from the front of the modem shelf.
k) Remove modem shelf
2. Installing the Shelf
a) Unpack the new modem shelf and screw into position re-using the screws
removed in 1.1 step 10.